Microfabricated double-tilt apparatus for transmission electron microscope imaging of atomic force microscope probe

Area of Science:

• Materials Science
• Nanotechnology
• Surface Science

Background:

• Atomic Force Microscopy (AFM) resolution is limited by probe tip geometry.
• Current methods for characterizing AFM probe tips are indirect or incompatible with advanced Transmission Electron Microscopy (TEM) systems.
• Accurate AFM probe characterization is crucial for advancing nanoscale measurements and applications.

Purpose of the Study:

• To develop a novel apparatus for high-resolution TEM observation of AFM probe tips.
• To enable atomic-scale characterization of AFM probe geometry, including crystallographic lattice fringes and tip profiles.
• To assess the variability in geometry among nominally identical AFM probes.

Main Methods:

• Designed and fabricated a thin sample holder compatible with TEM tilting stages.
• Utilized Transmission Electron Microscopy (TEM) to image AFM probe tips at atomic resolution.
• Employed sample tilting in TEM to obtain detailed crystallographic and profile information of the probe tips.

Main Results:

• Successfully demonstrated atomic-scale characterization of AFM probe crystal structures using TEM with sample tilting.
• Observed significant variations in the radius of curvature for probes from the same batch, ranging from 1.4 nm to 50 nm.
• Validated the capability of the new apparatus to overcome limitations of previous sample holders.

Conclusions:

• The developed TEM apparatus enables precise, atomic-scale characterization of AFM probe tips.
• Significant geometric variability exists even within batches of nominally identical AFM probes.
• Accurate probe characterization is essential for understanding and improving AFM measurement reliability and performance.